Printing mechanism

ABSTRACT

The present invention relates to a printing mechanism for simultaneous order printing (i.e. synchronous printing in all denominations) for calculating machines or the like or for use as output devices at data terminals or the like and provides means for maintaining a positive engagement between a drive transmitting member and setting means for type carriers by the action of a control member which will be moved out of an active position when the selected type carriers have been brought into their printing position. A substantial advantage is attained through this arrangement in comparison with known structures for similar use in which excessive efforts may be necessary to overcome compound spring action. A further advantage is that any time lag caused by the inertia of spring-actuated parts will not occur in transmitting the drive to the type carriers.

ijiiited States Patent 1191 Hjerpe 1 May 1, 1973 PRINTING MECHANISM 3,456,583 7/1969 Priebs ..101/94 [75] Inventor: Curt Hjerpe, Molndal, Sweden I Przmary Examiner-William B. Penn [73] Assignee: Facit AB, Atvidaberg, Sweden b & D b

[22] Filed: Dec. 16, 1970 [57] ABSTRACT [21] Appl. No.: 98,598 I The present mvention relates to a printing mechanism for simultaneous order printing (i.e. synchronous [30] Foreign Application E)rim'ity Data printing in all denominations) for calculating Dec. 18, 1969 Sweden ..17478/69 machines or the like or for use as Output devices at data terminals or the like and provides means for [52] U.S.Cl. ..l0l/93 MN maintaining a Positive engagement between a drive [51] Int. Cl. ..B41f 5/06 transmitting member and Setting means for yp [58] Field of Search ..101/93 R, 93 MN, riers y the action of a control member which will be 101/93 Q94 95 96 moved out of an active position when the selected type carriers have been brought into their printing [56] References Cit d position. A substantial advantage is attained through this arrangement in comparison with known structures UNITED STATES PATENTS for similar use in which excessive efforts may be 2,165,922 7/1939 (iarbell ..101/93 MN necessary evereeme Compound Spring action A 2 1 5 923 7 1939 Game" h v /9 further advantage is that any time lag caused by the 2,338,943 H1944 Hughes ..101/96 inertia of spring-actuated parts will not occur in trans- 2,82l,909 2/1958 Grosse ..101/93 R mitting the drive to the type carriers. 2,832,283 4/1958 Westinger et a1. 101/93 MN 3,232,223 2/1966 Thevis ..101/94 9 Claims, 6 Drawing Figures 21212d2d4a412b 1/ Patented May 1, 1973 6 SheetsSheet 1 Patented May 1, 1973 6 Sheets-Sheet 2 5 2 F l EI 4 ffmhV/JKJ Patented May 1, 1973 6 Sheets-Sheet 4 M/l/f'A rae c0127 mmepr Patented May 1, 1973 6 Sheets-Sheet 5 m m w E 5 E z:

6 Sheets-Sheet 6 PRINTING MECHANISM The present invention relates to a printing mechanism for calculating machines and the like or for use as output device at data terminals and the like, comprising at least one type carrier capable of different settings, setting means for the type carrier, a drive transmitting member located at the type carrier and operatively engageable with said setting means, and means for securing the type carrier during printing in a set position corresponding to a selected type.

In known printing mechanism of the aforementioned kind the drive transmitting member at the type carrier is held in a releasable operative engagement with the setting means by a spring the tension of which must be overcome when the type carrier is arrested in the selected position and the drive transmitting member shall be moved out of its engagement with the setting means. When a printing mechanism of this type comprises a plurality of type carriers the spring load will become of particular significance when several or all type carriers shall be arrested in the like set-up position. In this instance the bias of all springs must be overcome simultaneously. This will involve an unfavorable impact stressing of the setting mechanism and its drive means. As the engagement between the drive transmitting member mounted at the type carrier and the setting mechanism is further dependent on spring tension a lag of the drive imparted to the type carrier may be caused at the beginning of the setting motion by reason of the great momentum produced when the printing mechanism is operated at great speed.

The drawbacks referred to above have been eliminated in a simple way in the printing mechanism of the invention. According to a chief characteristic of this invention the drive transmitting member is positively held in engagement with the setting means by the action of a control member which is releasable through said securing means upon fixing the type carrier in a position corresponding to a selected type setting.

Two suitable embodiments of the invention will now be described with reference to the annexed drawings.

In the drawings I FIG. 1 is a side elevation view in partial section of one embodiment of the present invention;

FIG. 2 is a side view of the invention as shown in FIG. 1 in a subsequent stage of operation;

FIG. 3 is a side view of the invention as shown in FIG. 1 in another stage of operation;

FIG. 4 is a side elevation view in partial section of another embodiment of the present invention;

FIG. 5 is a side view of the invention as shown in FIG. 4 in a subsequent stage of operation; and

FIG. 6 is a side view of the invention as shown in FIG. 4 in yet another subsequent stage of operation.

Both embodiments illustrate the same basic structure in a printing mechanism, preferably a mechanism for simultaneous order printing such as the structure disclosed in US. Patent Application Ser. No. 840,203, filed July 9, 1969 by the same inventor, now US. Pat. No. 3,633,499. Only those components belonging to a single denomination and those components common to all denominations have been illustrated, insofar they are ofimportance for understanding the invention.

In both embodiments the types 1 of the printing mechanism form a complete set on each type carrier 2 and are held for longitudinal displacement in a holder 2a mounted at the type carrier. Each type carrier is freely pivoted on an axle 3 common to all type carriers. Axle 3 is itself pivotally mounted at its ends to a pair of vertical housing walls 50 (only one shown). A setting bail 4 is provided comprising a pair of bellcrank shaped end plates 4b (only one shown), the end plates being fixed in an aligned manner to respective ends of axle 3 adjacent the inner surface of each wall 50. A pair of rods 4a, 4c are mounted between the plates and extend transversely to the set of type carriers parallel to axle 3. Rod 4c engages printing hammers (not shown) such as those shown in US. Pat. No. 3,633,499 referred to above and cocks them upon suitable rotation of axle 3. The hammers and associated structure are not shown since such apparatus forms no part of the present invention. The function of rod 4a is explained in greater detail hereinbelow.

The type carriers 2 can be swung through any angle corresponding to a selected type, and their both extreme end positions are determined by a stationary rod 5 providing a stop means for the radial edges 2e of a circumferential recess formed in the hub portion of each type carrier 2.

A latch member 7 is provided for each type carrier 2 and is pivotally mounted at a stationary axle 6. This latch member 7 engages in its activated position by means of a hook-shaped portion formed thereon a row of teeth 2f formed at the type carrier, said teeth being correlated to the types 1. A lever 9 is pivotally mounted on a second stationary axle 8. On being swung in the clockwise direction by means of a tension spring 10 the lever 9 will rock latch member 7 counterclockwise into its activated position wherein it engages the teeth 2f. A common return bail 11 for all levers 9 is pivotally mounted on the axle 6 carrying the latch members 7. When the bail 11 is swung clockwise by non-illustrated means known in the art it will return by means of a rod all levers 9 in a counterclockwise motion whereby the latch members '7 are disengaged from the teeth 2f.' At this return movement an armature 9a mounted on each lever 9 is moved into engagement with a corresponding stationary electromagnet 9b so as to be held thereby in an inactive position against the bias of the spring 10 when the electromagnet is activated.

In the embodiment illustrated by FIGS. 1 to 3 a drive transmitting or dog member 12 is pivotally mounted at the type carrier 2 at the hub portion thereof on a stub shaft 12d integral with the hub portion which is received by a bore formed at one end of the drive transmitting or dog member 12. The drive transmitting member l2'is formed with a recess in its upper edge spaced from its pivot and engaging in the activated position of the member 12 shown in FIG. I the setting bail rod 4a. The edge portion of the member 12 facing the axle 3 is shaped with an arcuate edge portion 12a. In the activated position of the member 12 illustrated in FIG. 1 this arcuate edge portion extends concentrically to the axle 3. The arcuate edge 12a is engaged by the rounded top end of a shank belonging to a substantially fork-shaped pawl 13 accomodating between its prongs 13a, 13b the axle 3 which serves for guiding the pawl. The latter is formed adjacent to its extremity distant from the member 12 with a hook projection which is latched on a laterally extending stud 9c provided at the lever 9 close to the axle 8. The pawl 13 is sustained in its latched position by a spring 14 and is also supported against its lateral edge by the axle 8. Upon clockwise rotation of the setting bail 4 by way of any conventional mechanically or electrically powered drive mechanism (not shown) coupled to shaft 3, the member 12 will be retained in the relative position shown in FIG. 1 wherein it engages the rod 4a, as the prong 13b of pawl 13 prevents it from swinging out of this engagement. A corresponding angular displacement will accordingly be imparted to the type carrier. On interruption of the current through the electromagnet 9b, the lever 9 will be swung clockwise by the spring 10, the latch member 7 thereby being compelled to swing counterclockwise into engagement with the corresponding tooth space of the teeth 2f. The type carrier accordingly will become arrested in the position corresponding to the selected type 1.

During the described motion of the lever 9 the stud 90 will move in underneath the axle 8 and will release the pawl 13. The latter will be forced downward by the action of the dog member 12, which is compelled to swing clockwise by the action of the setting bail rod 4a as the latter follows up its setting movement.

The return travel of each type carrier 2 is initiated by reversing the direction of the rotation of the drive mechanism thereby reversing the direction of rotation of shaft 3. On the return travel, after printing, of the lever 9 and of the latch 7 from the position illustrated in FIG. 2 the stud 9c will slide along the adjacent lateral edge of pawl 13, spring 14 being additionally tensioned and urging the pawl back toward its latched position.

I This return movement of pawl 13 is prevented, however, by the dog member 12 which is sustained in its depressed inactive position during the initial stage of the return motion by the action of the rod 4a of the setting bail which abuts in the corresponding condition of the printing mechanism an upper arcuate edge portion 12b of the member 12. When, on its counterclockwise return travel the rod 4a reaches the recess formed in the upper edge of member 12 the latter will be reset by the action of the pawl 13 and spring 14 into the position shown in FIG. 1. In this position the 'rod 4a is brought into engagement with a shoulder 2d formed at the type carrier 2. The latter is positively moved back thereby to its initial position during the remaining part of the return movement.

When printing shall not be carried out in any denomination all levers 9 remain in their inactive positions, and the pawl 13 will be kept latched on the stud 9c. The dog member 12 will retain its engagement with the rod 4a of the setting bail while the edge portion of the member 12 abutting the .pawl 13 and concentric with the axle 3 slides against the top of the corresponding prong 13b of pawl 13' until the type carrier 2 strikes the abutment rod with one radial edge of the recess 2e. Thereby a recess 12c formed in the bottom edge 12a of the member 12 will become opposed to the prong 13b of pawl 13. The member 12, as illustrated in FIG. 3, can now be swung free of engagement with the setting bail rod 4a. A continued motion of the setting bail will be permitted thereby, notwithstanding that the type carrier has been arrested in its uppermost end position. The return of the member 12 into active position is carried out automatically during the return motion of setting bail 4 when the rod 4a is brought into engagement within upward projection 12d formed at the member 12 (FIG. 1).

In the embodiment just described the lever 9 is actuated by the drive transmitting member 12 with the intermediary of the pawl 13 and the stud 90. A quite opposite functioning takes place in the embodiment illustrated in FIGS. 4 to 6 and shall now be described.

In this second embodiment the drive transmitting or dog member denoted 15 is displaceable towards and away from the rod 4a radially of the axle 3 and is guided by the axle 3 and a lateral stud 2b extending from the type carrier 2. The member 15 has an oblique cam surface 15a for engaging the rod 4a succeeded by an arcuate edge portion 15b concentric with the axle 3 in the inactive position of the member 15. The opposite edge portion 15c of the member 15 is arc-shaped, as well. This edge portion is concentric with the axle 3 when the dog member 15 takes up the activated position illustrated in FIG. 4. The arcuate edge portion 15c is adapted to engage slidingly one extremity of a pawl 16 that corresponds to the pawl 13 of the embodiment first described. The pawl 16 engaging with an edge portion the axle 8 is formed at its extremity distant from the member 15 with a hook-shaped portion for engaging a stationary transverse rod 17 in the printing mechanism and is held in such engagement by a tension spring 18. The pawl 16 furTher is provided with a laterally extending stud 16a projecting beneath an abutment surface 9d at the right hand portion of the lever 9 which is of a somewhat modified shape in comparison with the lever of the embodiment first described. In the initial position illustrated in FIG. 4 the said abutment surface 9d is located directly above the stud 16a of the pawl 16. The latter is held in locking engagement with rod 17 by the spring 18 and engages at the same time the axle 8 as well as the arcuate edge portion 15c of the dog member 15. The latter thus is prevented in this position of the pawl 16 from being moved away from the rod 4a. The type carrier 2consequently will be carried along by the setting bail 4 in the clockwise setting motion of the latter. When the current through the electromagnet 9b is interrupted the lever 9 will be swung by the spring 10 into the position shown in FIG. 5 wherein the latch 7 is moved into 'engagement with the teeth 2f. Also, the abutment surface 9d of the lever 9 will strike the stud 160, the pawl 16 thereby losing its engagement with the rod 17. The dog member 15 is moved by the action of the rod 4a against the edge portion 15a relative to the axle 3. The pawl 16 will be displaced thereby, guided by the axle Band the rod 17.

The lower arcuate surface of the dog member 15 is continued by a steppeddown portion at a less radial distance from the axle 3. The edge portion 15c will discontinue by that reason its engagement with the pawl I6 when the type carrier reaches its corresponding angular position, i.e. when the type carrier is arrested in its uppermost position determined by the upper radial recess edge 2e abutting the rod 5..The drive transmitting member is free to be moved away from the setting bail rod 4a, thereby permitting the continued movement of the setting bail as illustrated in FIG. 6. On return of the type carrier to the initial position shown in FIG. 4 by the cooperation between the rod 4a and the shoulder 2d at the type carrier as described with reference to the first embodiment, the dog member will be brought back by the pawl 16 into its active position through the force of the spring 18 as soon as the lever 9 has resumed its position shown in FIG. 4 by the action of the return bail l l.

The invention is not restricted to the embodiments described above and illustrated in the drawings but can be varied as to its details within the scope of the appended claims.

What I claim is:

1. A printing mechanism comprising:

at least one rotatably mounted type carrier supporting a plurality of type characters thereon;

drive means for rotating said type carrier in a path of motion to a predetermined position associated with a particular type character including an elongate member mounted for rotation about an axis parallel to said elongate member, said elongate member extending transversely to said at least one type carrier;

means for latching said type carrier in said predetermined position;

means cooperating with said latch means for activating said latch means;

a dog member mounted on said type carrier movable between a first position wherein it is coupled to said elongate member for movement therewith and a second position uncoupled from said elongate member, so that upon coupling, said drive means will rotate said type carrier;

a pawl member movable between an active and inactive position having one end contacting a surface portion of said dog member so that when said pawl member is in said active position said dog member is maintained in said first position coupled to said elongate member; and

means provided on said latch activating means and pawl member for locking said pawl'member in said active position, said locking means adapted to become unlocked upon activation of said type carrier latch means.

2. A printing mechanism as claimed in claim 1 comprising at least one type carrier with a shape substantially of a circular sector being pivotally supported on an axle rotatable by said elongate member, wherein the surface portion of the dog member cooperating with the pawl member is substantially coaxial with the axle of the type carrier when said dog member is in said first position.

3. A printing mechanism as claimed in claim 1, wherein the pawl member has one end portion on which is formed said means for locking said pawl in said active position and an opposite end portion, a part of which is shaped for engaging said surface portion of the dog member, which opposite end portion is pivotally and displaceably journalled on the axle of the type carnor.

4. A printing mechanism as claimed in claim 1, wherein the pawl member is substantially hook-shaped and is pivotally and'displaceably journalled on an axle disposed outside the type carrier and is kept in said active position by means of a spring, and further including means to rock said pawl around the axle upon the actuation of said latch means thereby permitting the dog to disengage from the elongate member.

A printing mechanism as recited lIl clalm 1 wherein said surface portion of said dog member is substantially parallel to the path of motion of a portion of said type carrier upon movement thereof when said dog member is coupled to said elongate member.

6. A printing mechanism as claimed in claim 5, wherein the elongate member is adapted to perform additional movement in the setting direction, and wherein the surface of the dog member engaging the pawl member has a step formed therein for cooperating with said pawl member for moving the dog member out of engagement with the elongate member.

7. A printing mechanism as recited in claim 1 wherein said means for locking said pawl member in the active position includes a stop formed on said latch activating engageable with hook means formed on said pawl member, said hook means being disengaged from the stop upon activation of said latch means.

8. A printing mechanism as recited in claim 1 wherein said actuation means includes a selectively energizable electromagnet and a spring, said spring having endsconnected to said latch means and a fixed support, said electromagnet, when energized, sustaining said latch means in said first unlatched position and when deenergi zed, said spring causing said latch means to move to said second latched position.

9. A printing mechanism as recited in claim 1 wherein said means for locking said 'pawl member in the active position includes a stop formed on said latch activating means engageable with hook means formed on said pawl member, said hook means being disengaged from the top upon activation of said latch means.

a n: a: v 

1. A printing mechanism comprising: at least one rotatably mounted type carrier supporting a plurality of type characters thereon; drive means for rotating said type carrier in a path of motion to a predetermined position associated with a particular type character including an elongate member mounted for rotation about an axis parallel to said elongate member, said elongate member extending transversely to said at least one type carrier; means for latching said type carrier in said predetermined position; means cooperating with said latch means for activating said latch means; a dog member mounted on said type carrier movable between a first position wherein it is coupled to said elongate member for movement therewith and a second position uncoupled from said elongate member, so that upon coupling, said drive means will rotate said type carrier; a pawl member movable between an active and inactive position having one end contacting a surface portion of said dog member so that when said pawl member is in said active position said dog member is maintained in said first position coupled to said elongate member; and means provided on said latch activating means and pawl member for locking said pawl member in said active position, said locking means adapted to become unlocked upon activation of said type carrier latch means.
 2. A printing mechanism as claimed in claim 1 comprising at least one type carrier with a shape substantially of a circular sector being pivotally supported on an axle rotatable by said elongate member, wherein the surface portion of the dog member cooperating with the pawl member is substantially coaxial with the axle of the type carrier when said dog member is in said first position.
 3. A printing mechanism as claimed in claim 1, wherein the pawl member has one end portion on which is formed said means for locking said pawl in said active position and an opposite end portion, a part of which is shaped for engaging said surface portion of the dog member, which opposite end portion is pivotally and displaceably journalled on the axle of the type carrier.
 4. A printing mechanism as claimed in claim 1, wherein the pawl member is substantially hook-shaped and is pivotally and displaceably journalled on an axle disposed outside the type carrier and is kept in said active position by means of a spring, and further including means to rock said pawl around the axle upon the actuation of said latch means thereby permitting the dog to disengage from the elongate member.
 5. A printing mechanism as recited in claim 1 wherein said surface portion of said dog member is substantially parallel to the path of motion of a portion of said type carrier upon movement thereof when said dog member is coupled to said elongate member.
 6. A printing mechanism as claimed in claim 5, wherein the elongate member is adapted to perform additional movement in the setting direction, and wherein the surface of the dog member engaging the pawl member has a step formed therein for cooperating with said pawl member for moving the dog member out of engagement with the elongate member.
 7. A printing mechanism as recited in claim 1 wherein said means for locking said pawl member in the active position includes a stop formed on said latch activating engageable with hook means formed on said pawl member, said hook means being disengaged from the stop upon activation of said latch means.
 8. A printing mechanism as recited in claim 1 wherein said actuation means includes a selectively energizable electromagnet and a spring, said spring having ends connected to said latch means and a fixed support, said electromagnet, when energized, sustaining said latch means in said first unlatched position and when deenergized, said spring causing said latch means to move to said second latched position.
 9. A printing mechanism as recited in claim 1 wherein said means for locking said pawl member in the active position includes a sTop formed on said latch activating means engageable with hook means formed on said pawl member, said hook means being disengaged from the top upon activation of said latch means. 